DE102021206181A1 - Procedure for detecting a manipulated or forged GNSS signal - Google Patents

Abstract

The invention relates to a method for detecting a manipulated or forged GNSS signal (1), comprising at least the following steps: a) Receiving a plurality of GNSS signals (1, 2) which are located at different positions in an environment around an own position of a GNSS -Antenna (3) arrive, b) determining at least one arrival angle (4) of at least one received GNSS signal (1, 2) using the plurality of GNSS signals (1, 2) received in step a), c) recognizing a manipulated or falsified GNSS signal (1) if the determined angle of arrival (4) does not match the expected GNSS satellite constellation.

Description

The invention relates to a method for detecting a manipulated or falsified GNSS signal, a computer program for carrying out the method, a machine-readable storage medium on which the computer program is stored and a localization device for a vehicle, the localization device being set up to carry out the method. The invention can be used in particular in GNSS-based localization systems for autonomous or semi-autonomous driving. The method can advantageously enable distributed detection of GNSS spoofing using vehicles.

State of the art

In the case of GNSS-based localization, the GNSS reception or the GNSS localization can be purposefully disrupted by third parties. In this context, in particular, the generation and transmission of manipulated and/or forged GNSS signals are known, which are also generally referred to as so-called “spoofing”. Specifically, spoofing is done with the aim of misleading a GNSS receiver, possibly without the GNSS receiver noticing the attack. Known approaches for detecting GNSS spoofing are generally expensive to implement and/or not yet robust enough for use in modern vehicles that are already set up for at least partially automated driving, for example.

One object of the invention is therefore the cost-effective and robust detection of manipulated or falsified GNSS signals.

Disclosure of Invention

1. a) Empfangen einer Mehrzahl von GNSS-Signalen, die an verschiedenen Positionen in einem Umfeld um eine Eigenposition einer GNSS-Antenne eintreffen,
2. b) Ermitteln mindestens eines Eintreffwinkels mindestens eines empfangenen GNSS-Signals unter Verwendung der in Schritt a) empfangenen Mehrzahl von GNSS-Signalen,
3. c) Erkennen eines manipulierten oder gefälschten GNSS-Signals, wenn der ermittelte Eintreffwinkel nicht zu der erwarteten GNSS-Satellitenkonstellation passt.

According to claim 1, a method for detecting a manipulated or forged GNSS signal is proposed here, comprising at least the following steps:

1. a) receiving a plurality of GNSS signals arriving at different positions in an environment around a self-position of a GNSS antenna,
2. b) determining at least one angle of arrival of at least one received GNSS signal using the plurality of GNSS signals received in step a),
3. c) Detection of a manipulated or falsified GNSS signal if the determined angle of arrival does not match the expected GNSS satellite constellation.

To carry out the method, steps a), b) and c) can be carried out, for example, at least once and/or repeatedly in the order given. Furthermore, steps a), b) and c), in particular steps b) and c), can be carried out at least partially in parallel or simultaneously. In particular, step a) can be carried out on the vehicle or by means of a GNSS antenna (or at least part of a GNSS receiver) of a vehicle. Steps b) and c) can also be carried out on the vehicle side and/or at least partially outside the vehicle, for example by a higher-level management device that can receive data from a number of vehicles.

The method is used in particular for (distributed or joint) detection of a manipulated or falsified GNSS signal with a number of vehicles. The GNSS antenna mentioned in step a) generally relates to the GNSS antenna of the driver's own vehicle. In particular, the method can contribute to or serve for the distributed (or joint) detection of GNSS spoofing by means of vehicles.

The method can advantageously contribute to the (mechanical) detection of GNSS spoofing and/or meaconing. For example, the manipulated or falsified GNSS signal can be a signal that is artificially generated by a (satellite-external) GNSS signal generator and, in particular, is transmitted to GNSS receivers as an alternative or in addition to (original) satellite signals. In this case, the GNSS signal generator can be used, for example, to completely simulate GNSS signals and/or to add at least one signal to received GNSS signals in a meaconing scenario. The method can, for example, help to detect meaconing attacks in which received GNSS signals are retransmitted. However, the method is not limited to this. Rather, the method can advantageously contribute to identifying whether spoofing of GNSS signals is currently (generally) taking place.

The method is used in particular to detect a manipulated or forged GNSS signal in the context of (own) localization of a (motor) vehicle based (at least also) on GNSS data. In this context, the method contributes in particular to improving the accuracy and/or reliability of the position result of the vehicle position. In particular, any manipulation of the vehicle position that may be present can be recognized or discovered from the self-localization. The vehicle can be an automobile, for example dles, which is preferably set up for at least partially automated and / or autonomous driving.

In step a), a plurality of GNSS signals are received, which arrive at different positions in an area surrounding a GNSS antenna's own position. In principle, (original) GNSS signals from one or more GNSS satellites (e.g. from satellites of the services GPS, GLONASS, Galileo, Beidou, etc.) can be received by the (own) GNSS antenna. Furthermore, manipulated or falsified GNSS signals can be received by the (own) GNSS antenna, for example those emitted by a spoofing device. Furthermore, at least those (original or manipulated or forged) signals can also be received that were previously received from another (stationary or variable in location or movable along the earth's surface) GNSS receiver or another GNSS antenna in the vicinity of the (own) GNSS antenna have been received. These signals can, for example, then be forwarded to the (own) GNSS antenna and/or a processing device (e.g.: control unit) or localization device connected to it (and thus received in step a) by way of example). Corresponding GNSS receivers or other GNSS antennas in the vicinity of the (own) GNSS antenna can be arranged, for example, in or on (other) vehicles in the vicinity of the GNSS antenna or on infrastructure elements. Alternatively or additionally, GNSS signals can be taken into account that were or are received by the same (own) GNSS antenna at different positions in the area around the current own position and/or at different times (virtual antenna array).

In step b), at least one angle of arrival of at least one received GNSS signal is determined, in particular estimated or calculated, using the plurality of GNSS signals received in step a). The at least one angle of arrival can include, for example, the azimuth and/or elevation angle of the relevant GNSS signal. The respective arrival angles can be determined for several or all GNSS signals from the plurality of GNSS signals. To determine the at least one angle of arrival, received GNSS signals can be transmitted from one vehicle to at least one other vehicle. In particular, to determine the at least one angle of arrival, distribution of received GNSS signals to surrounding vehicles can be carried out, in particular with the aim of forming a so-called GNSS antenna array with several vehicles, which is preferably able to determine the angle of arrival (angle of-Arrival) of a received signal.

In step c), a manipulated or falsified GNSS signal is detected if the determined angle of arrival does not match the expected GNSS satellite constellation. The expected GNSS satellite constellation can result, for example, from stored or defined data which describe the respective current positions of the GNSS satellites. Corresponding data can include, for example, ephemeris data and/or almanac data. With the determined angle of arrival (angle-of-arrival) it can advantageously be reliably determined whether the received signal originates from a legitimate sender of the signal (the satellite) or from a spoofing device. For example, a minimum arrival angle and/or an expected arrival angle range and/or an expected arrival angle can be determined for the expected GNSS satellite constellation. In particular, if the determined angle of arrival is flatter or smaller (compared to the horizontal) than the minimum angle of arrival and/or is outside the expected angle of arrival range and/or deviates significantly (at least 10% or at least 20%) from the expected angle of arrival, a manipulated or forged GNSS signal or the use of a spoofing device can be inferred.

In a step d), an at least also GNSS-based localization can be adapted depending on whether or if a manipulated or forged GNSS signal was detected in step c). In this case, for example, the GNSS-based localization can be (down)weighted (for example compared to GNSS-independent localization methods that are also used). Alternatively or additionally, signals that have been identified as being manipulated or forged can be excluded from localization.

An advantage of the method can also be seen in particular in the fact that it can be carried out with hardware that is usually already on board modern vehicles, such as GNSS sensors, GNSS antennas, V2X or mobile radio. The method can thus advantageously be used at low cost and with little integration effort.

A vehicle that is suitable for carrying out the method or takes part in carrying out the method preferably has at least one communication device (V2X or mobile radio) in order to receive information from other vehicles and/or from infrastructure elements and/or from a cloud receive. In addition, such a vehicle usually has at least a GNSS sensor with which GNSS signals can be received. Furthermore, such a vehicle can have, for example, at least one surroundings sensor (camera, LIDAR, RADAR and/or ultrasound), with which the relative distance between vehicles can be determined, for example.

According to an advantageous embodiment, it is proposed that in step a) at least raw GNSS signals are also received that were received and forwarded by GNSS receivers that are located in the area around the own position and are independent of the GNSS antenna. The term raw signal describes here in particular unprocessed or non-preprocessed signals as they are received directly from the GNSS satellite. In this context, raw GNSS signals are advantageously forwarded or distributed, for example to determine the angle of arrival between vehicles. In particular, there is no need to distribute GNSS data (position data) that have already been evaluated. Furthermore, to determine the angle of arrival, a comparison can be made between GNSS raw signals that were received at different positions, for example from different vehicles. Such a comparison of the raw signals allows the advantage over a comparison of positioning results (position data) that the information provided by different receivers or vehicles (here raw signals) cannot be influenced to the same extent. With current spoo⌷ng technology, on the other hand, it would basically be possible to influence several vehicles to the same extent. As a result, the vehicle positions would make sense in relation to one another, but they would still be wrong.

According to a further advantageous embodiment, it is proposed that the GNSS antenna is arranged in or on a vehicle. The vehicle can be, for example, a motor vehicle, such as an automobile. The vehicle can be set up for at least partially automated or autonomous driving. In this context, it can also be provided, for example, that the vehicle has only a single GNSS antenna. In particular, in this context, the vehicle does not have a physical antenna array. The vehicle can also have a (single) processing device assigned to the GNSS antenna. The processing device can be set up in such a way that it can carry out a so-called virtual antenna array determination with information from a single GNSS antenna.

Furthermore, it can be provided that in step a) GNSS signals are received from other vehicles located in the vicinity of the host vehicle. In this context, it can also be provided that the relative positions of the other vehicles in relation to one's own vehicle are determined and taken into account when determining the at least one angle of arrival. The relative positions can be determined, for example, using at least one environment sensor of the driver's vehicle. Furthermore, the vehicles can advantageously exchange the relative positions determined (by the respective vehicle) with one another via a communication link (for example via radio). This can advantageously contribute to being able to integrate even more antennas into an array.

According to a further advantageous embodiment, it is proposed that in step c) it is determined whether the angle of arrival is plausible. The angle of arrival can be considered plausible in particular if it is steeper or larger (compared to the horizontal) than a minimum angle of arrival and/or is within an expected range of angles of arrival and/or essentially corresponds to an expected angle of arrival.

According to a further aspect, a computer program for carrying out a method presented here is proposed. In other words, this relates in particular to a computer program (product), comprising instructions which, when the program is executed by a computer, cause the latter to execute a method described here.

According to a further aspect, a machine-readable storage medium is proposed, on which the computer program proposed here is deposited or stored. The machine-readable storage medium is usually a computer-readable data carrier.

According to a further aspect, a localization device for a vehicle is proposed, the localization device being set up to carry out a method described here. The localization device can, for example, comprise a computer and/or a control unit (controller) which can execute commands in order to carry out the method. For this purpose, the computer or the control device can, for example, execute the specified computer program. For example, the computer or the control unit can access the specified storage medium in order to be able to run the computer program. The localization device can, for example, be a component of a motion and position sensor that can be or is arranged in particular in or on a vehicle net, or be connected to such a sensor for the exchange of information.

The details, features and advantageous configurations discussed in connection with the method can accordingly also occur in the computer program presented here and/or the storage medium and/or the localization device and vice versa. In this respect, full reference is made to the statements there for a more detailed characterization of the features.

• 1: einen beispielhaften Ablauf des hier vorgestellten Verfahrens,
• 2: ein beispielhaftes Szenario bei dem das hier vorgestellte Verfahren zur Anwendung kommt,
• 3: einen Ablauf einer bevorzugten Ausführungsform des hier vorgestellten Verfahrens, und
• 4: ein Fahrzeug mit einer hier beschriebenen Lokalisierungseinrichtung.

The solution presented here and its technical environment are explained in more detail below with reference to the figures. It should be pointed out that the invention should not be limited by the exemplary embodiments shown. In particular, unless explicitly stated otherwise, it is also possible to extract partial aspects of the facts explained in the figures and to combine them with other components and/or findings from other figures and/or the present description. They show schematically:

• 1 : an example of the procedure presented here,
• 2 : an exemplary scenario in which the method presented here is used,
• 3 : a sequence of a preferred embodiment of the method presented here, and
• 4 : a vehicle with a localization device as described herein.

1 shows a schematic of an exemplary sequence of the method presented here. The procedure is used to detect a manipulated or falsified GNSS signal 1 (cf. 2 ). The order of steps a), b), c) and, if applicable, d) shown with blocks 110, 120 and 130 and optional block 140 is exemplary and can be run through at least once in the shown order to carry out the method, for example.

In block 110, according to step a), a plurality of GNSS signals 1, 2 are received (cf. 2 ), which arrive at different positions in an environment around a proper position of a GNSS antenna 3 . In block 120, according to step b), at least one arrival angle 4 of at least one received GNSS signal 1, 2 is determined using the plurality of GNSS signals 1, 2 received in step a). In block 130, according to step c), detection occurs a manipulated or falsified GNSS signal 1 if the determined angle of arrival 4 does not match the expected GNSS satellite constellation.

In particular, determining the angle of arrival 4 includes determining the direction from which a signal 1, 2 arrives. For this purpose it is advantageous if (as in the 2 case outlined) several antennas 3, 5, which pick up this signal, are available. The direction from which the signal 1, 2 was emitted can be determined in a particularly advantageous manner from the times (at which the signal was received by the different antennas) and the arrangement of these antennas 3, 5 relative to one another.

In this context, it is also preferred that a corresponding communication takes place between the vehicles 5, 6 involved. At least the times (at which the signal was received by the different antennas) can also be transmitted or exchanged with one another from vehicle to vehicle, in particular in addition to the received GNSS raw data or GNSS raw signals. The communication between the vehicles 5, 6 can take place, for example, by means of V2V or mobile radio. In addition, determining the relative positions of the vehicles 5, 6 to one another can contribute to determining the direction.

In principle, however, it is also possible for a single vehicle 6 with a single antenna 3 to be able to determine the angle of arrival. For this purpose, it is preferable to use GNSS signals 1, 2 that were or are received by the same (own) GNSS antenna 3 at different positions in the area around the current own position and/or at different times. A corresponding procedure can be described with the term "virtual antenna array".

In the optional block 140, according to an (optional) step d), an at least also GNSS-based localization can be adjusted depending on whether or if a manipulated or forged GNSS signal was detected in step c).

2 shows a schematic example of a scenario in which the method presented here is used. In addition to one own vehicle 6, two further vehicles 7 are shown as an example. In addition, a GNSS satellite 9 and a GNSS spoofer 8 are shown for illustrative purposes. The method according to the example 2 for the distributed detection of GNSS spoofing using the example of three vehicles 6, 7 are used.

In step a), at least raw GNSS signals can also be received that were received and forwarded by GNSS receivers 5 that are located in the area around the own position and are independent of the GNSS antenna 3 . The GNSS receivers 5 can be arranged in or on the other vehicles 7, for example. The GNSS antenna 3 can be part of the driver's vehicle, for example. In particular, the GNSS antenna 3 can be arranged in or on one or one's own vehicle 6 . In this case, the vehicle 6 can only have a single GNSS antenna 3 . The representation after 2 In this context, FIG. 10 also represents an example of the fact that, if necessary, as in step a), GNSS signals 1, 2 can be received from other vehicles 7 located in the area around one's own vehicle 6.

It can be provided that the positions of the other vehicles 7 relative to the host vehicle 6 are determined and taken into account when determining the at least one angle of arrival 4 . Furthermore, it can be determined in step c) whether the angle of arrival 4 is plausible.

3 shows schematically a sequence of a preferred embodiment of the method presented here.

bezeichnet werden. Jedes GNSS-Signal 2 kann unter Anderem Informationen darüber beinhalten, welcher Satellit 9 dieses Signal abgestrahlt hat.In block 210, a GNSS signal 1, 2 can be received. At a point in time t, a vehicle 6, 7 (hereinafter also referred to as symbol: v _i ) can receive one or more GNSS signals 1, 2 via its GNSS receiver 3, 5, which are received from satellites 9 and/or from a spoofer 8 to be broadcast. Furthermore, the set of signals 1, 2 received from v _i at time t with $S_{v_i}^t$

be designated. Each GNSS signal 2 can contain, among other things, information about which satellite 9 emitted this signal.

bezeichnet werden.In block 211, the relative distances from surrounding vehicles 7 can be determined. At any point in time t, each vehicle v _i (for example vehicle 6) can use environment sensors to detect vehicles 7 in the area and determine their respective relative position. The set of surrounding vehicles 8 detected by vehicle v _i at time t together with their relative positions (to v _i ) can be used as $R_{v_i}^t=\left\{{\mathrm{<figure-callout\; id="1"\; label="right\; v"\; filenames="DE102021206181A1\_0009.png"\; state="\{\{state\}\}">right</figure-callout>}}_{v_{}},...,{\mathrm{right}}_{v_n}\right\}$

be designated.

In block 212 the received GNSS signal can be shared with other vehicles 7 . At any point in time t at which a vehicle v _i (for example vehicle 6) has received a GNSS signal 1, 2 by means of a GNSS receiver or GNSS antenna 3, the vehicle v _i can be used to determine the angle of arrival or angle Communicate appropriate and/or necessary information about this signal to all vehicles in an of-arrival calculation. In particular, this information can contain the time and the carrier phase at which the signal was received. This information can be referred to below as gi. The information can be communicated, for example, with V2X/V2V messages and/or with a geocast that is provided, for example, via a cloud service. Alternatively or cumulatively, the information can be shared with a (different) radio technology, such as WLAN, Bluetooth, mobile communications, etc.

In particular since the GNSS antenna 3 can be mounted at a different location for each vehicle type and different vehicles can also use different GNSS antennas, the installation position and/or GNSS antenna-specific information can also be contained in gi, for example.

bei der Übermittlung auch die relativen Entfernungen von umliegenden Fahrzeugen 7 $R_{v_i}^t$

mit anderen Fahrzeugen geteilt werden. Hierdurch können vorteilhaft auch Fahrzeuge mit in ein lokales Modell aufgenommen werden, die sich ggf. sogar außerhalb der Reichweite der Fahrzeugeigenen Umfeldsensoren befinden, aber von anderen Fahrzeugen 7 in der Region vermessen werden können.For example, in addition to $G_i^t$

when transmitting, also the relative distances of surrounding vehicles 7 $R_{v_i}^t$

be shared with other vehicles. As a result, vehicles that are possibly even outside the range of the vehicle's own environment sensors can also be included in a local model, but can be measured by other vehicles 7 in the region.

von einem anderen Fahrzeug v_j (zum Beispiel Fahrzeug 7) empfangen hat, dieses zu der Menge der empfangenen Signale $M^t=\left\{g_1^t,\dots ,g_n^t\right\}$

hinzugefügt werden.In block 213, received GNSS signals 1, 2 from other vehicles 7 can be received. At any point in time t at which a vehicle v _i (for example vehicle 6) receives a GNSS signal $G_i^t$

received from another vehicle _vj (e.g. vehicle 7) adds this to the set of received signals $M^t=\left\{G_1^t,...,G_n^t\right\}$

to be added.

sowie der von den Fahrzeugen 7 empfangenen Signale M^t das Fahrzeug 6 für jeden Datenpunkt $g_i^t$

∈ M^t der zum eigenen Fahrzeug relativen Positionen der GNSS-Antennen berechnet werden, mit denen die Signale aus M^t empfangen wurden. Beispielhafte mathematische Formulierungen zur Berechnung des Angle-of-Arrival mittels eines Antennen-Arrays bei dem die Positionen der einzelnen Antennen nicht die exakte Position sondern Schätzwerte der Position darstellen, sind grundsätzlich bekannt.In block 214, the angle of arrival 4 can be determined or the angle of arrival can be calculated for, in particular, each received GNSS signal 1, 2. In particular, with the help of the relative position of the surrounding vehicles 7 $R_{v_I}^t$

and the signals M ^t received from the vehicles 7 the vehicle 6 for each data point $G_i^t$

∈ M ^t of the positions of the GNSS antennas, relative to the own vehicle, with which the signals from M ^t were received. Exemplary mathematical formulations for calculating the angle-of-arrival using an antenna array, in which the positions of the individual antennas do not represent the exact position but estimate values of the position, are known in principle.

In other words, this can also be described in particular in such a way that in block 214 the GNSS signals 1, 2 received with one's own GNSS antenna 3, the relative positions (relative to one's own vehicle 6 or one's own GNSS antenna 2) to the GNSS Antennas 5 of the other vehicles 7 and copies of the GNSS signals 1, 2 received from these antennas 5 are used in order to determine the angle of arrival 4 or to calculate the angle-of-arrival for, in particular, each received GNSS signal 1, 2 . In particular, phase measurements of the GNSS signals 1, 2 can contribute to the determination or calculation.

In block 215, the received signal can be decoded, in particular for assigning the signal to a satellite. Each GNSS signal usually contains information about the satellite that is transmitting or has transmitted it. How this information from the received signal can be interpreted in order to be able to assign it to a satellite can be found in the corresponding Interface Control Documents (ICDs) of the corresponding GNSSs.

In block 216, a calculation of the position of the corresponding satellite can be performed. The orbital parameters of the trajectories of satellites are generally known, such as being publicly available on the Internet and/or published (in some cases with greater accuracy) via special commercial service providers. In addition, the satellites themselves transmit orbital parameters via so-called navigation data messages. If it is known which satellite transmitted a signal at a certain time, these orbital parameters can be used to calculate the satellite position at the time of transmission and thus also the angle of arrival or angle-of-arrival of an original (i.e. not fake) signal or the (in the case of the relevant satellite constellation) to be expected arrival angle or angle-of-arrival to be expected. This is usually in the two components azimuth and elevation.

In block 217, a comparison can be made using the angle of arrival determined (in step b) and the calculated position of the satellite. For example, as part of a comparison of the (expected) angle of arrival (azimuth and elevation angle) of the satellite with the angle of arrival (azimuth and elevation angle) determined or estimated in step b), for example using a (virtual) antenna array, for the received Signal can be determined, whether the signal was broadcast from the direction of the satellite, or whether it is a fake signal, which was broadcast from another direction.

Accordingly, a case distinction can be made in block 218, in which it is checked whether the corresponding angles match at least to a certain minimum extent or not.

In block 219, surrounding vehicles can be warned of spoofed signals. If, for example, a comparison of the estimated angle of arrival or angle-of-arrival and the position of the satellite shows that the signal is fake, other vehicles in the area can also be warned of this signal, for example. This can be done, for example, with V2X / V2V messages and/or with a geocast that is e.g. provided via a cloud service and/or with another wireless technology such as WLAN, Bluetooth, cellular, etc.

In block 220, a corresponding GNSS signal (identified or recognized as fake) can be excluded from the position calculation. If a received satellite signal is recognized as being forged, it can be excluded from the GNSS position calculation of the (own) vehicle, for example.

The method can thus be used in particular for vehicles to exchange received GNSS signals with surrounding vehicles with the aim of forming a (virtual) antenna array from these with the aim of determining an angle-of-arrival to create a fake one from a legitimate GNSS signal.

As an alternative or in addition to distributing the GNSS signals to surrounding vehicles, all vehicles can also transmit the received signals to a central location (a server/cloud service). This can then calculate the (respective) angle of arrival or angle-of-arrival and compare this with the expected angle of arrival or angle-of-arrival. As a result, this server/cloud service can report to the appropriate vehicles (and preferably also to all other vehicles in the region) which signals are fake GNSS signals.

As an alternative or in addition to a number of vehicles, the method can also be carried out with a number of infrastructure elements (for example roadside units or infrastructure cameras) or with a mixture of vehicles and infrastructure elements.

Alternatively or in addition to a set of (different) vehicles, the method can also be used on just one vehicle with just one antenna are running. For this purpose, the signals can be observed in particular over time and the trajectory of the vehicle can be estimated over time using onboard sensors (such as IMU and odometer). A corresponding procedure is also generally referred to as a “single antenna based virtual antenna array” or as a “synthetic aperture”. As soon as a single vehicle has detected a fake signal, it can also pass this on to other road users in the region via V2X or another communication technology. In this case, too, it is advantageous to collect the individual measurements from vehicles in a cloud service and, if necessary, to determine the angle of arrival or angle-of-arrival there. Due to the larger amount of measurement data, the calculated data can advantageously be checked for plausibility with one another in order to avoid false detections as far as possible.

Furthermore, for a particularly advantageous location of the spoofer, several different sets of vehicles can be used in order to construct several different virtual antennas that receive the same fake signal. So these can be used advantageously to determine the location of the spoofer. This location can then be automatically reported to the relevant authorities and/or to other road users and/or to a cloud service for criminal prosecution.

4 FIG. 1 shows a vehicle 6 with a localization device 10 described here. The localization device 10 is set up to carry out a method described here.

A method and a localization device are thus described here, with which counterfeit (=spoo⌷ng) Global Navigation Satellite System (GNSS) signals can advantageously be reliably detected. This can make it possible to ignore them in the position calculation, which makes it significantly more difficult for an attacker (spoofer) to get a victim to carry out an incorrect determination of their own position.

According to a particularly advantageous embodiment, several GNSS receivers 3, 5 installed in several vehicles 6, 7 receive the same GNSS signals 1, 2 and exchange them with one another via a radio channel. In addition, the vehicles 6, 7 can use vehicle sensors (e.g. radar, lidar, ultrasound, camera, etc.) in order to determine the relative position of the vehicles 6, 7 among one another. This advantageously results in each vehicle 6, 7 being in possession of the received GNSS signals 1, 2, each recorded by different antennas 3, 5 at different locations (an antenna array) at the same time. Because the relative positions of the antennas are known to one another (due to the vehicle positions), the angle of arrival or angle of arrival can be determined particularly advantageously for each GNSS signal. In particular, this indicates the direction from which a received signal was emitted. A fake GNSS signal is detected in particular when the determined angle of arrival or angle-of-arrival does not match the known position of the satellite that should actually be broadcasting this signal.

Claims (10)

Method for detecting a manipulated or forged GNSS signal (1), comprising at least the following steps: a) Receiving a plurality of GNSS signals (1, 2) which arrive at different positions in an environment around a proper position of a GNSS antenna (3), b) determining at least one arrival angle (4) of at least one received GNSS signal (1, 2) using the plurality of GNSS signals (1, 2) received in step a), c) Recognition of a manipulated or forged GNSS signal (1) if the determined angle of arrival (4) does not match the expected GNSS satellite constellation. procedure after claim 1 , wherein in step a) at least GNSS raw signals are also received, which were received and forwarded by GNSS receivers (5) that are located in the area around the own position and are independent of the GNSS antenna (3). procedure after claim 1 or 2 , wherein the GNSS antenna (3) is arranged in or on a vehicle (6). procedure after claim 3 , wherein the vehicle (6) has only a single GNSS antenna (3). Method according to 3 or 4, wherein in step a) GNSS signals (1, 2) are received from other vehicles (7) located in the area surrounding the host vehicle (6). procedure after claim 5 , wherein the relative positions of the other vehicles (7) to the host vehicle (6) are determined and taken into account when determining the at least one angle of arrival (4). Method according to one of the preceding claims, it being determined in step c) whether the angle of arrival (4) is plausible. Computer program for carrying out a method according to one of the preceding claims. Machine-readable storage medium on which the computer program claim 8 is saved. Localization device (10) for a vehicle (6), wherein the localization device (10) for carrying out a method according to one of Claims 1 until 7 is set up.

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